Geographic Range

Common marmosets are New World primates. Their original range was limited to north eastern Brazil, but habitat destruction in that area is widespread. Wild populations of the common marmoset are now located in south eastern Brazilian coastal rainforest. (Parker, 1990)

Habitat

Physical Description

The common marmoset has a body length of about 12 - 15 cm, with a tail length of 29.5 - 35 cm. Distinguishing characteristics of common marmosets include white ear tufts, and a white blaze on the forehead. Their head fur is usually dark brown, while their back fur is a greyish brown color with light transverse striping. They also have very pronounced transverse tail stripes.

Reproduction

It was originally thought that common marmosets were monogamous creatures, forming pair bonds and raising their offspring as a team. This was believed because captive marmosets only bred successfully in a pair situation. However, it has recently been discovered that the common marmoset, along with other species of marmosets and tamarins, is actually polyandrous (one female mates with multiple males). In the wild, groups of two males and a female form in order to mate and rear offspring. The female mates nearly equally with both males while in estrus.

The twins combined can equal up to 40% of the female's body weight. The males assist the female in carrying the infants, and it is generally thought that polyandry in this species is due to the large size of these babies and the energy needed to raise them.

Behavior

Common marmosets are diurnal, and generally live in groups of 2-13 individuals which may include mated polyandrous groups and their offspring. The most outstanding feature of common marmoset behavior is nonmaternal infant care (also found in other callitrichid primates). Males and siblings are quick to assist mother common marmosets with infant care, and indeed, it seems that this help is necessary for infant survival. (Smuts et al., 1987)

Communication and Perception

Food Habits

While the common marmoset generally feeds on tree sap, this species has also been found to eat insects, spiders, fruit, flowers, and nectar. Less frequently, they have been observed feeding on small lizards, bird's eggs, nestlings, and frogs.

Economic Importance for Humans: Positive

When zoos are able to obtain these tiny creatures, they are very popular attractions.

Economic Importance for Humans: Negative

Because they have adapted to life on the edge of the forests of south eastern Brazil, common marmosets have also learned to take advantages of the plantations in the area. In greater numbers, they may become pests to human farmers. (Smuts et al., 1987)

Conservation Status

Common marmosets are one of the most endangered callitrichid species. The complete destruction of their habitat in north eastern Brazil has severely threatened the species, but their numbers in reserves in south eastern Brazil seem to be growing.

Other Comments

It is only very recently that humans have been able to obtain any information about this species at all. Because of their rarity and size, they are difficult to study in the wild, and comparisons between captive and field studies have proved that their behavior varies between the two. (Evans, 1986)

Contributors

Glossary

Neotropical

living in the southern part of the New World. In other words, Central and South America.

arboreal

Referring to an animal that lives in trees; tree-climbing.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

cooperative breeder

helpers provide assistance in raising young that are not their own

diurnal

active during the day, 2. lasting for one day.

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

herbivore

An animal that eats mainly plants or parts of plants.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

polyandrous

Referring to a mating system in which a female mates with several males during one breeding season (compare polygynous).

rainforest

rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

social

associates with others of its species; forms social groups.

tactile

uses touch to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

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The Animal Diversity Web is an educational resource written largely by and for college students. ADW doesn't cover all species in the world, nor does it include all the latest scientific information about organisms we describe. Though we edit our accounts for accuracy, we cannot guarantee all information in those accounts. While ADW staff and contributors provide references to books and websites that we believe are reputable, we cannot necessarily endorse the contents of references beyond our control.

This material is based upon work supported by the
National Science Foundation
Grants DRL 0089283, DRL 0628151, DUE 0633095, DRL 0918590, and DUE 1122742. Additional support has come from the Marisla Foundation, UM College of Literature, Science, and the Arts, Museum of Zoology, and Information and Technology Services.